Gorenje D 16M, Installation And User Manual

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11.Leak detection methods.
The following leak detection methods are deemed acceptable for systems
containing flammable refrigerants. Electronic leak detectors shall be used to
detect flammable refrigerants, but the sensitivity may not be adequate, or may
need re-calibration. (Detection equipment shall be calibrated in a refrigerant-free
area.) Ensure that the detector is not a potential source of ignition and is suitable
for the refrigerant used. Leak detection equipment shall be set at a percentage
of the LFL of the refrigerant and shall be calibrated to the refrigerant employed
and the appropriate percentage of gas (25 % maximum) is confirmed. Leak
detection fluids are suitable for use with most refrigerants but the use of
detergents containing chlorine shall be avoided as the chlorine may react with
the refrigerant and corrode the copper pipe-work. If a leak is suspected, all
naked flames shall be removed/ extinguished. If a leakage of refrigerant is found
which requires brazing, all of the refrigerant shall be recovered from the system,
or isolated (by means of shut off valves) in a part of the system remote from the
leak. Oxygen free nitrogen (OFN) shall then be purged through the system both
before and during the brazing process.
12.Removal and evacuation.
When breaking into the refrigerant circuit to make repairs or for any other
purpose conventional procedures shall be used. However, it is important that
best practice is followed since flammability is a consideration. The following
procedure shall be adhered to:
Remove refrigerant;
Purge the circuit with inert gas;
Evacuate;
Purge again with inert gas;
Open the circuit by cutting or brazing.
The refrigerant charge shall be recovered into the correct recovery cylinders.
The system shall be flushed with OFN to render the unit safe. This process may
need to be repeated several times. Compressed air or oxygen shall not be used
for this task.
Flushing shall be achieved by breaking the vacuum in the system with OFN and
continuing to fill until the working pressure is achieved, then venting to
atmosphere, and finally pulling down to a vacuum. This process shall be
repeated until no refrigerant is within the system. When the final OFN charge is
used, the system shall be vented down to atmospheric pressure to enable work
to take place. This operation is absolutely vital if brazing operations on the pipe-
work are to take place.
Ensure that the outlet for the vacuum pump is not close to any ignition sources
and there is ventilation available.
13.Charging procedures.
In addition to conventional charging procedures, the following requirements
shall be followed. Ensure that contamination of different refrigerants does not
occur when using charging equipment. Hoses or lines shall be as short as
possible to minimise the amount of refrigerant contained in them.
Cylinders shall be kept upright.
Ensure that the refrigeration system is earthed prior to charging the system with
refrigerant. Label the system when charging is complete (if not already).
Extreme care shall be taken not to overfill the refrigeration system.
Prior to recharging the system it shall be pressure tested with OFN. The system
shall be leak tested on completion of charging but prior to commissioning. A
follow up leak test shall be carried out prior to leaving the site.
14.Decommissioning.
Before carrying out this procedure, it is essential that the technician is
completely familiar with the equipment and all its detail. It is recommended good
practice that all refrigerants are recovered safely. Prior to the task being carried
out, an oil and refrigerant sample shall be taken in case analysis is required prior